Experience gained during their own air landings caused the Germans
to regard attack as the only effective means of combating airborne
operations. Their fight against Allied airborne operations demonstrated
the wisdom of this rule. The Germans failed to crush the Allied
invasion, not because this principle proved erroneous, but because
the necessary forces were either lacking or could not be brought
up quickly enough or because German counterattacks were not conducted
properly. In many instances, however, these attacks did impede
the progress of Allied airborne operations; at Arnhem they brought
Allied operations to a complete standstill.

The most vulnerable period of any air landing is the interval
between the jump and assembling of the forces into organized units
under a unified command. In order to exploit this weakness, German
field service regulations stipulated that any unit within range
of enemy troops which had landed from the air should immediately
attack since every moment's delay meant an improvement in the
situation for the enemy. This method proved to be fundamentally
sound. It led to success whenever the enemy landed in small scattered
groups or whenever the landing was effected in the midst or in
the immediate vicinity of German reserves ready for action. But
these tactics are not successful if the defending forces available
for immediate action are too weak to defeat enemy troops vastly
superior in number, or if the defenders are too far from the point
of landing to be able to exploit the enemy's initial period of
weakness. Then there is no longer any purpose in dissipating the
defending forces in small isolated attacks or in doggedly fighting
the enemy. It now becomes necessary to launch a systematic counterattack.

Speed in carrying out a counterattack against enemy airborne troops
is essential, because it is certain that the enemy's fighting
strength will be increased continuously by means of additional
reinforcements brought in by air. In general, only motorized reserves
are successful in arriving in time. If the enemy's air forces
succeeds, as it did in Normandy, in delaying the arrival of reserves,
the chances for success dwindle. The elements which are nearest
the enemy have the task of defending important terrain features
against air-landed troops, maintaining contact with them, and
determining the enemy situation through reconnaissance until all
necessary arrangements for the counterattack have been made.

The counterattack should be conducted under unified command and,
as far as possible, launched as a converging attack from several
sides and supported by the greatest possible number of heavy weapons,
artillery, and tanks; it is directed against an enemy who is well
prepared and whose weakness lies merely in that he may be troubled
by lack of ammunition and in that his heavy weapons, in general,
are inferior in number since he has not established contact with
those elements of the invading force which are advancing on land.
To prevent the enemy from establishing contact is therefore highly
important. If this fails, the defender's chances for success are
considerably less. There are no cases during World War II in which
the Germans succeeded in annihilating airborne enemy troops after
they had established contact with their forces on the ground.

The greatest stumbling block encountered by the Germans in combating
Allied airborne operations in the West was the superiority of
the Allied air force. German failure to eliminate this air force,
or even to clear the skies temporarily, led to the most serious
delays in bringing up reserves. The general scarcity of mobile
reserves, combined with the fact that they were tied down elsewhere
by order of the German High Command, led to the result that in
Normandy counterattacks were made too feebly, too late, or not
at all. The success of the German counterattacks at Arnhem was
due to the energetic action and unified command of Army Group
B; the fortunate coincidence that two SS panzer divisions were
in the immediate vicinity; the weather, which prevented Allied
air intervention; and the resistance offered by the German troops
at Nijmegen which prevented the prompt establishment of contact
between Allied ground troops and airborne elements.